If the screen goes black but still has haptic feedback (vibration on touch) then it could be a software issue see bad app above. If there is no haptic feedback make sure the phone did not simply die charge it for while and try using the phone again. If the phone is not dead there may be an underlying hardware issue with the internal components of the touch screen caused by a drop or the phone's age.

If your phone has a loose slide track the most common symptom is that one corner of the phone will slide higher than the other and it alternates back and for until the phone reaches the top. In order to fix this repair the slide tracks.

If the slide track goes up only a fraction of the way and stops then something is impeding the path. The only repair is to go inside the phone and remove the object blocking the path. Repair slider guide.

If the phone is left on the charger for a substantial amount of time after the battery has been fully charged, for example overnight, then the battery would release a large amount of heat. Over-Charging not only causes the phone to overheat it can also ruin the battery.

If the phone is left exposed to direct sunlight for extended periods of time, the phone could overheat damaging the phone. To avoid this do not leave the phone sitting out in the sun for extended periods of time.

If the solution to the first software malfunction did not solve your problem then another way to try and fix the error message and unresponsive camera would be to do a factory reset on your phone. This will delete all contacts and information on the phone so do a device backup to an SD card to save all information.

my nokia n900 is badly activated on rebooting during ssu package updating due to net failior. There are no other function but allways repeat rebooting process only with a yellow icon on status bar .Is it possible to overcome? How? Please give instruction.